The present invention relates to a bumper beam assembly system for a vehicle, and more particularly, to a bumper beam assembly system which is capable of minimizing repair costs of a corner part when the corner portion is crashed at a low speed.
A bumper beam assembly represents a functional part protecting a frame when a vehicle is crashed at a low speed and is usually provided with a bumper beam and a stay. In this case, the bumper beam may absorb most of crash energy, and the stay may absorb the rest of the crash energy. That is, the bumper beam that is directly crashed may firstly absorb the crash energy, and the stay through which the bumper beam is connected to the frame to support the bumper beam may secondly absorb the crash energy.
Required performance of the bumper beam assembly constituted as described above may be tested through two tests such as a low speed crash regulation test and a repair cost evaluation crash test which is performed by General Insurance Association (Insurance Institute for Highway Safety (IIHS) and Research Council for Automobile Repairs (RCAR)). In particular, since the low speed crash test performed by General Insurance Association may evaluate the repair costs after a low speed crash to utilize a standard for appropriating a premium, and thus the low speed crash test has a large effect on vehicle sales. Thus, most automobile manufacturers are putting a great deal of effort to develop a bumper beam assembly having cheap repair costs in consideration of the repair cost evaluation (commercial value evaluation) performed by General Insurance Association.
In this regard, IIHS may offset a central portion of a vehicle bumper and about 15% of an overall width of the vehicle by using a bumper dummy to perform a low speed crash test at about 10 KPH and about 5 KPH, as shown in FIG. 1, thereby appropriating the repair costs and announcing to mass communication. For reference, a result of the low speed crash test performed by IIHS is exemplified in FIG. 2. Generally, a bumper beam having excellent performance may have repair costs required when the bumper beam assembly and the bumper cover assembly are replaced without being damaged in itself after the test is performed by IIHS.
In recent years, a bumper beam formed of a low-weight, high-performance plastic composite material is widely applied so as to improve fuel efficiency. Since the plastic composite material is lighter than steel, the plastic composite material may be effective in aspects of vehicle fuel efficiency. However, since the plastic composite material is relatively expensive when compared to that of the steel, the repair cost evaluation performed by General Insurance Association may cause poor results due to the high replacement costs. Also, the bumper beam formed of the plastic composite material may have high strength through compression-molding. However, the bumper beam may be weak in strength at both ends thereof due to the compression-molding. As a result, the damaged beam and deformed stay should be replaced in the 15% offset test performed by IIHS (hereinafter, referred to as an “IIHS 15% offset test”).
In detail, bumper assemblies having various shapes are disclosed in Korean Patent Application Nos. 10-2008-0069637, 10-2009-0081580, 10-2007-0002937, 10-2009-0093518, 10-2008-0059204 and 10-2011-0122098. However, in the related arts above described, as shown in FIG. 3, simple and usual steel beams or plastic composite material beams are provided. Also, since an extruded crash box for a vehicle is disposed behind the bumper beam, the bumper beam may be firstly crashed and damaged, and then the stay or crash box may be deformed or damaged in the IIHS 15% offset test. Therefore, costs for replacing the whole bumper beam assembly may be required.